1.Explain why the reactivity of group 7 decreases as you move down the group. Try to use the sentence starters here: When group 7 elements react, their atoms….

As you move down the group, the outer shells get…

Therefore the force of attraction between the shells and the nucleus is….

This makes attracting an extra electron…

Consequently, reactivity…​

Answer:

3 releases energy

Explanation:

An electron in an energy level has a definite amount of energy associated with it at that level.

Electrons can undergo transitions from one level to another. However, when the electron changes its state, it must absorb or emit the exact amount of energy which will bring it from the initial to the final state.

When the electron is excited, it moves from the ground state to an excited state, it must absorb energy. On returning from an excited state to a lower level or the ground state, energy is emitted, giving rise to a line in the spectrum.

Answer: 3 because it releases energy

A chemical equation is said to be balanced if the quantity of each type of atom in the reaction is the same on both the reactant and product sides. In a balanced chemical equation, the mass and the charge are both equal. P₄ + 4NaOH + 2H₂O → 2PH₃ + 2Na₂HPO₃.

A chemical equation is said to be balanced if the quantity of each type of atom in the reaction is the same on both the reactant and product sides. In a balanced chemical equation, the mass and the charge are both equal.

A chemical equation must balance according to the rule of conservation of mass. According to the rule, mass cannot be generated or removed during a chemical process.

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Answer:

A small mass of positive charge was discovered in the center of the atom.

Explanation:

Atoms is the combination of protons, neutrons, as well as electrons particles. The particles that are in the centre of atom is Protons and neutrons, which made up the nucleus, this nucleus is surrounded by electron.

The discovery that directly caused scientists to revise this model of the atom is that A small mass of positive charge known as proton, and a positive charge particle was discovered by Ernest Rutherford, in the center of the atom in the year 1900. Ernest Rutherford through his research resulted to splitting of the atom during nuclear reaction and proton was discovered.

Answer:

Magnesium, calcium and sodium.

Explanation:

Magnesium, calcium, sodium, and other beneficial minerals are the substances present in drinking water. Different regions have different fluoride concentration in their water such as in sea water, fluoride level is 1.1 mg/L while in surface water, the concentration is 0.01–0.3 ppm. Yes, fluoride is soluble in water. No, fluoride should not be added to drinking water because it harm for health. All the questions can be answered by science because it is related to chemistry.

Answer: Nuclear

Explanation:

Nuclear energy generates power through fission, which involves splitting uranium atoms to produce energy. The heat released by fission is used to create steam that rotates turbine to generate electricity.

The energy produced by nuclear plants is carbon free but the products formed are radioactive and hence their transportation, storage, and disposal is a big problem. It can not be dumped like normal waste.

Answer:

I hope it helps u

Explanation:

The advantages of using natural gas rather than coal are the following,

Car and Motorcycle engines are controlled by a chemical reaction which is controlled by gasoline and oxygen.

A chemical reaction may be defined as a process that significantly involves the chemical transformation of one set of chemical substances to another. This process involves the utilization of substances known as reactants that are transformed into other substances known as products.

The fuel in cars and motorcycles delivers the source of energy to them in order to move from one place to another. This fuel significantly contains gasoline which reacts with atmospheric oxygen and results in a small explosion which derives some sort of energy that is finally consumed by the vehicle's engine.

Apart from this, the combustion of fuel is also facilitated in the presence of oxygen which liberates extremely high amounts of carbon dioxide in the atmosphere. This reaction has also occurred in the engines of vehicles.

Therefore, car and Motorcycle engines are controlled by a chemical reaction which is controlled by gasoline and oxygen.

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Answer:

I FINNALY GOT MY HANDS ON THE AWNSER, dont

copy word for word though Explanation:

Simulation of a reaction is a chemical reaction modeling or demonstration tool, using various software to better understand the molecular structure and the physical and chemical properties of the molecule. Here the actual reaction is N2 + 3H2 -----> 2NH3. In the simulation reactions, the nitrogen and hydrogen molecules in the actual reaction are described by different colored circles or dots and the bonds are produced using a single, double or triple line that touches each molecule and gives an appearance like the reactants and the products' ball and stick model. Example: Molecule of nitrogen as o---triple line---o. A molecule of hydrogen as O———O. Chemical symbols such as N and H are expressed in Actual Chemical Reaction, N2 and H2 and the bonds are represented by single, double or triple lines that do not impact the atoms in the molecule as follows: Nitrogen Molecule: N -triple Bond- N. Hydrogen Molecule: H - H.

Salt added : 14.5 g

Given

17% salt solution

71 ml water

Required

salt needed

Solution

%mass = (mass solute : mass solution) x 100%

71 ml water = 71 g water(density = 1 g/ml)

mass solute = x

[tex]\tt 17\%=\dfrac{x}{x+71}\times 100\%\\\\0.17(x+71)=x\\\\0.17x+12.07=x\\\\0.83x=12.07\\\\x=14.5[/tex]

Answer:

from one metallic element to a different nonmetallic element

Explanation:

For example NaCl is ionic compound in which Na metal donate electron to Cl non metal

Answer:

The answer is C, both krypton and neon.

Explanation:

I got the answer wrong and my teacher told me that c is the right answer choice

Ions can be made by single element or covalently bonded group of elements. The covalently bonded group of elements is called polyatomic ions or polyatomic atoms. Therefore, the correct option is option C.

Any species that contain charge whether it is positive charge or negative charge is called ions. The example of polyatomic ions are sulfate, phosphate, nitrate etc.

Cation is the species that loose electron and attain positive charge while anion is a species which gain electron and attains negative charge so when anion and cation combine in fixed ration the the overall charge of the molecule is zero that is molecule is neutral, the charge over cation and anion is also called oxidation state.

Rb react as cation Rb ⁺ with electron distribution as [Kr] after removal of 1 electron from s orbital. F react as anion F⁻ with electron distribution [He] 2s² 2p⁶ which is equal to electronic configuration of neon.

Therefore, the correct option is option C.

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Answer:

There are 0.00047212 wig in 3.0099 dumps.

Explanation:

In this problem, we need to convert 3.0099 dumps to wigs.

6375.23 dumps = 1 wig (given)

1 dump = (1/6375.23) wig

To convert 3.0099 dumps to wigs, multiply 3.0099 by (1/6375.23).

3.0099 dumps = [tex]\dfrac{1}{6375.23}\cdot3.0099[/tex]

= 0.00047 wig

Hence, there are 0.00047212 wig in 3.0099 dumps.

Answer:

The correct answer is  - 32 cells.

Explanation:

In the meiosis type of cell cycle or cell division, a single parent cell divides into four daughter cells, unlike mitosis. Meiosis takes place in the reproductive or sex cell and called reduction division.

As we know each cell divide into four daughter cells.

1  reproductive cell = 4 daughter cells

2 reproductive cell = 8 daughter cells

Now each daughter cell undergo meiosis than each cell will produce 4 cells so,

8 daughter cells will produce:

8 *4 = 32 cells.

Thus, the correct answer is  - 32 cells.

Answer:

The answer is p⁴.

Explanation:

You have to apply Indices Law :

[tex] {a}^{m} \times {a}^{n} ⇒ {a}^{m + n} [/tex]

For this question :

[tex] {p}^{3} \times {p}^{1} [/tex]

[tex] = {p}^{(3 + 1)} [/tex]

[tex] = {p}^{4} [/tex]

Answer:

a. forces acting on the object

Answer:

22g of  2

C

O

2

have  3.011×1023

3.011

×

10

23

  2

C

O

2

molecules.

Explanation:

Hope this helps! ^^

Answer:

divide the moles by gram to get molar mass

use calculator and get yo ans

Answer:

Explanation:

Tough question.

The answer is very dependent on the temperature of the water. At 0o C, less than 5 grams is soluble in water.

The curve increases as the temperature increases. At 80oC about 35 grams  is soluble in water 100 mL of water.  So Ba(OH)2 is very soluble at higher temperatures.

Maybe the question can be resolved just a little better at room temperature. The solubility is still less than 5 grams / 100 mL. That makes it slightly soluble or more soluble than other things.

So to answer the question, you need to specify the temperature. I would say it is, but be prepared to defend your answer.

In case you don't know what Calcium Is:

a silver-white divalent metal, occurring combined in limestone, chalk, gypsum, etc., occurring also in vertebrates and other animals, as a component of bone, skeletal mass, shell, etc., and as a necessary element in nerve conduction, heartbeat, muscle contraction, and many other physiological functions.

Calcium can be found:

Calcium is a soft white chemical element found in bones and teeth

answer:

Using the definition..calcium may be used in the human body by nerve conduction, heartbeat, muscle contraction, and many other physiological functions.

·.•·°.hope this helped!!!·.•·°.

Answer:

See Explanation

Explanation:

Let us consider the first two reactions, the initial concentration of CO was held constant and the concentration of Hbn was doubled.

2.68 * 10^-3/1.34 * 10^-3 = 6.24 * 10^-4/3.12 * 10^-4

2^1 = 2^1

The rate of reaction is first order with respect to Hbn

Let us consider the third and fourth reactions. The concentration of Hbn is held constant and that of CO was tripled.

1.5 * 10^-3/5 * 10^-4 = 1.872 * 10^-3/6.24 * 10^-4

3^1 = 3^1

The reaction is also first order with respect to CO

b) The overall order of reaction is 1 + 1=2

c) The rate equation is;

Rate = k [CO] [Hbn]

d) 3.12 * 10^-4 = k [5 * 10^-4] [1.34 * 10^-3]

k = 3.12 * 10^-4  /[5 * 10^-4] [1.34 * 10^-3]

k = 3.12 * 10^-4/6.7 * 10^-7

k = 4.7 * 10^2 mmol-1 L s-1

e) The reaction occurs in one step because;

1) The rate law agrees with the experimental data.

2) The sum of the order of reaction of each specie in the rate law gives the overall order of reaction.

Answer:

i believe it is b as well

Explanation:

Answer:

i dont see the model bro

Explanation:

Answer:

The current model of the atom shows an atom that is mostly empty space. In the center is a small nucleus made of protons and neutrons.

Explanation:

Explanation:

A chemical reaction where two chemical compounds exchange ions with each other is called a double displacement reaction.

Also, when an insoluble salt is formed due to chemical reaction between two chemical compounds is called a precipitation reaction.

For example, [tex]NaCl(aq) + AgNO_3(aq) \rightarrow NaNO_3(aq) + AgCl(s)[/tex]

Here, ions are exchanged between the compounds [tex]NaCl[/tex] and [tex]AgNO_3[/tex] . Also, [tex]AgCl[/tex] is the precipitate formed.

Answer:

B - Covalent bonds

Explanation:

Covalent bonds are a class of chemical bonds where valence electrons are shared between two atoms, typically two nonmetals. The formation of a covalent bond allows the nonmetals to obey the octet rule and thus become more stable.

Answer:

this is a multiple choice question where are the answers

Explanation:

Answer:

state symbol meaning

[s] solid

liquid

gas

aq] aqueous dissolved in water

Explanation:

often chemical equations are written showing the state that each substance is in. the [s] sign means that the compound is a sold. the l sign means the substance is a liquid. the aq sign stands for aqueous in water and means the compound is dissolved in water

thank me later.

Answer:

D.

Explanation:

because gametes are sexual reproducing cells, like sperm and egg cells are gametes. and those make up 50% of you

To solve this we must be knowing each and every concept related to gamete. Therefore, 50% of a mammal’s genetic material comes from each gamete. The correct option is option D.

Sex cells are another frequent name for gametes. The fundamental name for them is "reproductive cells," and they are a component of human reproductive system.

These gametes are indeed the ones that aid in sexual reproduction and they are charge of creating the zygote, a whole new cell that is known as a zygote. These cells are haploid cells, in which each and every gamete typically carries a unique version of the chromosomes. 50% of a mammal’s genetic material comes from each gamete.

Therefore, 50% of a mammal’s genetic material comes from each gamete. The correct option is option D.

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Answer:

It's called a theory because it has not been proven yet. so we can not claim it to be a fact without proof.

Answer: There is no concrete evidence.

Explanation: If we could do an experiment and create the Big Bang and watch it happen and study it, it would be law. It's for the same reason that evolution is considered a theory. We are not watching it take place and there is no eye witness account of evolution happening because evolution happens over millions and millions of years. If we could sit here and watch the universe be created without need for simulations or theories, then it would be law.

Answer:

8

Explanation:

From the question given above, the following data were obtained:

t–butyl ion = (CH₃)₃C⁺

Number of valence electron =?

The valence electron(s) talks about the combining power of an element or compound as the case may be.

Considering the t–butyl ion, (CH₃)₃C⁺ we can see that it has a charge of +1 indicating that it has given out 1 electron to attain the stable octet configuration which has a valence electrons of 8. Thus, the valence electron of t–butyl ion, (CH₃)₃C⁺ is 8